Linear Programming Lindo Problem

The State of Virginia is one of the largest produces of wood furniture in the United States, with the furniture industry accounting for 50% of value added to wood materials. Over the past 40 years the inventory volume of wood in Virginia’s forests has increased by 81%. Today, 15.4 million acres, which is well over half of the state, are covered in forest. Private owners hold 77% of this land. When making decisions about which trees to harvest, forestry professionals consider many factors and must follow numerous laws and regulations.
The figure below depicts a tract of forested land that has been sectioned off into 16 harvestable areas, indicated by dashed lines. Area E provides the only access to the forest via a paved road, so any timber cut ultimately must be transported out of the forest through Area E. Currently, there are no roads through this forest. So to harvest the timber, forest roads must be built. The allowable routes for these roads are also shown in the figure below. They are determined largely by the geography of the land and by the location of streams and wildlife habitat.
Not all areas of the forest have to be harvested. However, to harvest any area, a forest road must be built to that area. The cost of building each section of forest road (in $1000s) is indicated in the figure. Also, note that road connecting G->K or K->G costs the same, $12,000. Finally, the value of the harvestable timber in each area is estimated as follows: